The present disclosure relates to the field of virology. In particular, the disclosure teaches methods of detecting the presence of a respiratory viral infection (e.g. by a coronavirus or influenza virus) in a subject, and methods of treating said respiratory viral infection.

The present invention relates to a method for determining the origin of glutamic acid in a sample and, in a broader sense, relates to a method for determining the origin of an amino acid. The present invention makes it possible to measure the stable isotope ratio, with a considerably higher accuracy than that of conventional methods, by measuring the δ13C of glutamic acid (amino acid) by elemental analysis-stable isotope ratio mass spectrometry (EA-IRMS) and measuring the δ15N by gas chromatography-stable isotope ratio mass spectrometry (GC-IRMS). In addition, the present invention makes it possible to determine the origin of glutamic acid (amino acid) by comparing the stable isotope ratio of the glutamic acid (amino acid) whose origin is unclear with the stable isotope ratio of glutamic acid (amino acid) whose origin is clear.

A data processing method for creating simulation data of a three-dimensional chromatogram for a sample containing a plurality of components. The data processing method includes a data preparing step of preparing chromatogram data and spectrum data of each of a plurality of the components, a parameter determining step of determining a parameter including a ratio of concentration of a plurality of the components in the sample to each other and separation degree of peaks of a plurality of the components on a chromatogram from each other, a data adjusting step of adjusting a peak area and a peak position of chromatogram data of each of a plurality of the components based on the parameter determined in the parameter determining step, and a matrix product step of calculating matrix product of a spectrum data group including spectrum data of each of a plurality of the components and a chromatogram data group including chromatogram data of each of a plurality of the components adjusted in the data adjusting step, and creating simulation data of a three-dimensional chromatogram for the sample based on a result of the calculation.

Provided herein chiral derivatization reagents for use in separating and detecting of amine containing enantiomers. The said chiral derivatization reagents provide a combination of improved detectable properties to facilitate various downstream analyses. In particular, the chiral derivatization reagents include at least one chiral carbon atom; at least one strongly basic moiety; at least one chromophore moiety or at least one fluorophore moiety; and at least one reactive group. The present disclosure further provides methods for analyzing amine-containing enantiomeric isomers using a chromatographic separation device and a mass spectroscopy.

Disclosed herein is a method for verifying the primary structure of a protein through comparative analyses between ion clusters observed in mass spectra and a series of simulated ion clusters deduced from its putative chemical formula. The method comprises the steps of: preparing a protein sample for mass spectrometric analyses; collecting mass spectra of the protein sample; obtaining master ion cluster from a plurality of ion clusters in the mass spectra; producing a series of simulated ion clusters according to the chemical formula of the protein; finding the best fit for the master ion cluster among the series of simulated ion clusters; and verifying if said best-fit simulated ion cluster corresponds to the chemical formula of the protein.

Microorganisms are prolific producers of natural products, a group of molecules that make up the majority of drugs approved by the FDA in the past 35 years. After decades of mining, the low-hanging fruit has been picked and so discovery of drug-like molecules from microorganisms has come to a near-halt. The reason for this lack of productivity is that most biosynthetic pathways that give rise to natural products are not active under typical laboratory growth conditions. These so-called ‘cryptic’ or ‘silent’ pathways are a major source of new bioactive molecules and methods that reliably activate them could have a profound impact on drug discovery. Disclosed herein is a rapid genetics-free method for eliciting and detecting cryptic metabolites using an imaging mass spectrometry-based approach. An organism of choice is challenged with elicitors from a small molecule library. The molecules elicited are then imaged by mass spec, which allows for rapid identification of cryptic metabolites. These are then isolated and characterized. Employing the disclosed approach activated production of cryptic glycopeptides from an actinomycete bacterium. The molecules that result, the keratinimicins and keratinicyclins, are metabolites with important structural features. At least two of these, keratinimicins B and C, are highly bioactive against several pathogenic strains. This approach will allow for rapid activation and identification of cryptic metabolites from diverse microorganisms in the future.

Quorum-sensing peptides are provided as diagnostic biomarkers, and quorum-sensing peptide inhibiting substances are provided for use in the treatment of metastasis of colorectal cancer in a subject, in particular a human subject. Methods for reducing metastasis of colorectal cancer in a subject include administering to the subject a microorganism that reduces or blocks activity of a pro-metastatic quorum-sensing peptide or a metabolite thereof present in a gastrointestinal tract or blood of the subject; and/or that reduces or blocks production of the pro-metastatic quorum-sensing peptide or the metabolite thereof in the gastrointestinal tract or blood of the subject. The pro-metastatic quorum-sensing peptide may include EntF or the metabolite EntF* of EntF.

This disclosure provides methods, systems, and compositions of matter for studying solvent accessibility and three-dimensional structure of biological molecules. A plasma can be used to generate marker radicals, which can interact with a biological molecule and mark the solvent-accessible portions of the biological molecule.

The invention relates to the detection of EGYR peptide in a biological sample as a measure of the presence and/or amount of LARP1 protein in the sample. Suitably, the invention relates to methods for quantitative measurement of LARP1 and LARP1-derived EGYR peptide by chromatography-tandem mass spectrometry. The invention also relates to peptide standards and their use in quantitative mass spectrometric analyses. The ability to detect the amount of LARP1 in a biological sample has application in detecting and monitoring cancer.

Set forth herein are glycopeptide biomarkers useful for diagnosing diseases and conditions, such as but not limited to, cancer (e.g., ovarian), an autoimmune disease, fibrosis and aging conditions. Also set forth herein are methods of generating glycopeptide biomarkers and methods of analyzing glycopeptides using mass spectroscopy. Also set forth herein are methods of analyzing glycopeptides using machine learning algorithms.